I always like the interpretation of Lex that dislikes Superman for several reasons:
1. Lex believes that Superman didn't earn his god-like power. Lex gained wealth and power through his own brilliance, cunning, ruthlessness, etc. In Lex's mind, Superman got his power because he was lucky enough to land on the right planet.
2. Lex sees Superman as a threat who is standing in the way of human progress.
3. Lex believes that with his brilliance and nearly unlimited resources, he could have solved all of humanity's problems and become it's savior, if not for that damn alien.